Rash.. That doesn’t seem to go away.. HELP

My daughter has had what seems like a diaper rash for almost 2 months long but I been constantly keeping up with her diaper changes etc but hasn’t gone away. so a week ago I took her to see her pediatrician and she said it might be an infection (yeast) well I been on it by cleaning her up and applying mupirocin 3x daily but it hasn’t gone away... I’ve tried destin, aquaphor, even the new zarbees rash ointment. Nothing seems to make it go away.. Has anyone experienced something similar? she is very itchy as well.